Every two years the Canadian Obesity Network holds its National Obesity Summit – the only national obesity meeting in Canada covering all aspects of obesity – from basic and population science to prevention and health promotion to clinical management and health policy.

Anyone who has been to one of the past four Summits has experienced the cross-disciplinary networking and breaking down of silos (the Network takes networking very seriously).

Of all the scientific meetings I go to around the world, none has quite the informal and personal feel of the Canadian Obesity Summit – despite all differences in interests and backgrounds, everyone who attends is part of the same community – working on different pieces of the puzzle that only makes sense when it all fits together in the end.

The 5th Canadian Obesity Summit will be held at the Banff Springs Hotel in Banff National Park, a UNESCO World Heritage Site, located in the heart of the Canadian Rockies (which in itself should make it worth attending the summit), April 25-29, 2017.

Yesterday, the call went out for abstracts and workshops – the latter an opportunity for a wide range of special interest groups to meet and discuss their findings (the last Summit featured over 20 separate workshops – perhaps a tad too many, which is why the program committee will be far more selective this time around).

Childhood and adolescent obesity – research conducted with children and or adolescents and reports on the correlates, causes and consequences of pediatric obesity as well as interventions for treatment and prevention.

Obesity in adults and older adults – prevalence studies and interventions to address obesity in these populations

Clinical management – clinical management of overweight and obesity across the life span (infants through to older adults) including interventions for prevention and treatment of obesity and weight-related comorbidities

Rehabilitation – investigations that explore opportunities for engagement in meaningful and health-building occupations for people with obesity

Diversity – studies that are relevant to diverse or underrepresented populations

eHealth/mHealth – research that incorporates social media, internet and/or mobile devices in prevention and treatment

Continuing in my miniseries on why obesity (defined here, as excess or abnormal body fat that affects your health) should be considered a disease, is the simple observation that obesity responds less to lifestyle treatments than most people think.

Yes, the internet abounds with before and after pictures of people who have “conquered” obesity with diet, exercise, or both, but in reality, long-term success in “lifestyle” management of obesity is rare and far between.

Indeed, if the findings from the National Weight Control Registry have taught us anything, it is just how difficult and how much work it takes to lose weight and keep it off.

Even in the context of clinical trials conducted in highly motivated volunteers receiving more support than you would ever be able to reasonably provide in clinical practice, average weight loss at 12 – 24 months is often a modest 3-5%.

Thus, for the vast majority of people living with obesity, “lifestyle” treatment is simply not effective enough – at least not as a sustainable long-term strategy in real life.

While this may seem disappointing to many (especially, to those in the field, who have dedicated their lives to promoting “healthy” lifestyles as the solution to obesity), in reality, this is not very different from the real-life success of “lifestyle” interventions for other “lifestyle” diseases.

Thus, while there is no doubt that diet and exercise are important cornerstones for the management of diabetes or hypertension, most practitioners (and patients) will agree, that very few people with these conditions can be managed by lifestyle interventions alone.

Indeed, I would put to you that without medications, only a tiny proportion of people living with diabetes, hypertension, or dyslipidemia would be able to “control” these conditions simply by changing their lifestyles.

Not because diet and exercise are not effective for these conditions, but because diet and exercise are simply not enough.

The same is true for obesity. It is not that diet and exercise are useless – they absolutely remain a cornerstone of treatment. But, by themselves, they are simply not effective enough to control obesity in the vast majority of people who have it.

This is because, diet and exercise do not alter the biology that drives and sustains obesity. If anything, diet and exercise work against the body’s biology, which is working hard to defend body weight at all costs.

Thus, it is time we accept this reality and recognise that without pharmacological and/or surgical treatments that interfere with this innate biology, we will not be able to control obesity in the majority of patients.

Whether we like it or not, I predict that within a decade, clinical management of obesity will look no different than current management of any other chronic disease. Most patients will require both “lifestyle” and probably a combination of anti-obesity medications to control their obesity.

This does not take away from the importance of diet and exercise – as important as they are, they are simply not enough.

Despite what “lifestyle” enthusiasts will have us believe, diet and exercise are no more important (or effective) for the treatment of obesity, than they are for the treatment of hypertension, diabetes, dyslipidemia, depression, or any other condition that responds to “lifestyle” interventions.

In the end, most patients will require more effective treatments to manage their obesity and all of the comorbidities that come with it. The sooner we develop and make accessible such treatments, the sooner we can really help our patients.

One of the most common fallacies about weight loss is that simply cutting your caloric intake by 500 Cal per day should result in a 1 lb weight loss per week.

This fallacy is based on the rathe simplistic notion that because 7 x 500 arithmetically happens to equal 3,500 Cal, which just happens to be approximately the caloric content of 1 lb of fat tissue, a reduction in weekly energy intake of 3,500 calories should lead to a 1 lb weight loss.

“For example, if a 5′6″, 30-year-old woman weighing 180 lb and consuming 2622 calories daily reduced her intake by 500 calories per day, the 3500-calorie rule would estimate her weight loss at 1 year to be almost 52 lb. At 10 years, the 3500-calorie rule would yield a negative body weight..”

Or, as I tell my patients, no one will continue losing weight till they disappear.

As regular reader of these page will appreciate, the simple reason why the 3500 Cal rule is wrong, is because the relationship between changes in caloric intake and weight loss is anything but linear. Rather, as daily caloric consumption decreases (or increases), metabolic demands adapt to compensate for this decrease (or increase), thereby limiting what happens to body weight.

This “dynamic” model of weight loss is nicely illustrated in the many validated predictors of weight loss available online (click here for an example).

Thus, based on such a model, in the above case, the actual expected weight loss at 1 year would only be around 12 lb with stabilization of a a 31-lb loss after 3 years.

Incidentally, these number, which in the above case correspond to about a 7% weight loss at one year and a 16% weight loss at 3 years are well in excess of what can generally be achieved with diet and exercise alone (those numbers being closer to 3-5% at 12-24 months).

As Allison and colleagues rightly point out, such inaccuracies (especially when propagated by reputable journals such as JAMA) mislead both health professionals and the public and do little more than promote unrealistic expectations about weight loss.

It is high time we abandoned simplistic “energy-in energy-out” models of obesity or weight management.

The 4th Canadian Obesity Summit (#COS2015) will provide the latest information on obesity research, prevention and management to scientists, health care practitioners, policy makers, partner organizations and industry stakeholders working to reduce the social, mental and physical burden of obesity on Canadians.

The COS 2015 program will include plenary presentations, original scientific oral and poster presentations, interactive workshops and a large exhibit hall. Most importantly, COS 2015 will provide ample opportunity for networking and knowledge exchange for anyone with a professional interest in this field.

CON-SNP consist of an extensive network within CON, comprising of over 1000 trainees organised in about 30 chapters at universities and colleges across Canada.

Students and trainees in this network come from a wide range of backgrounds and span faculties and research interests as diverse as molecular genetics and public health, kinesiology and bariatric surgery, education and marketing, or energy metabolism and ingestive behaviour.

Over the past eight years, since the 1st COSM was hosted by laval university in Quebec, these meetings have been attended by over 600 students, most presenting their original research work, often for the first time to an audience of peers.

Indeed, it is the peer-led nature of this meeting that makes it so unique. COSM is entirely organised by CON-SNP – the students select the site, book the venues, review the abstracts, design the program, chair the sessions, and lead the discussions.

Although a few senior faculty are invited, they are largely observers, at best participating in discussions and giving the odd plenary lecture. But 85% of the program is delivered by the trainees themselves.

Apart from the sheer pleasure of sharing in the excitement of the participants, it has been particularly rewarding to follow the careers of many of the trainees who attended the first COSMs – many now themselves hold faculty positions and have trainees of their own.

As my readers are well aware, I regularly attend professional meetings around the world – none match the excitement and intensity of COSM.

I look forward to another succesful meeting as we continue to build the next generation of Canadian obesity researchers, health professionals and policy makers.